Sanderling Plan - Western Hemisphere Shorebird Reserve Network

CONSERVATION THREATS
Sanderlings face a number of conservation threats especially during the nonbreeding
season. Because the Sanderling is a relatively long-lived species with low reproductive rates,
even small changes in adult survival can have significant impacts on its population dynamics.
Hence, it is imperative to understand and target those factors that may potentially affect (or
already be affecting) adult survival.
The most likely threats causing declines in Sanderling are:
1) Habitat loss and degradation;
2) Human disturbance;
3) Contaminants and disease;
4) Climate change
5) Predation
HABITAT LOSS AND DEGRADATION
Coastal habitats (particularly sandy beaches), upon which Sanderlings rely for most of
their lifecycle, are being heavily developed and fragmented by human activities. Since the early
1900s, more than 50% of U.S. coastal wetlands have been lost, with much heavier losses in
certain states, for example New Jersey, North Carolina, Florida (Helmers 1993) and most of
California. Habitat impacts are occurring at two scales: specific and widespread. At the specific
scale, habitat loss (e.g., from development) or habitat degradation (e.g., oil spills) at important
staging areas could have potentially catastrophic impacts. However, no less damaging is the
cumulative effect of widespread alterations occurring throughout the nonbreeding range from
small-scale, piecemeal development or conversion of habitat (Morrison and Ross 1989). These
widespread threats will increase as human population and pressures on coastlines increase.
Hence, a prudent conservation strategy for Sanderlings must likewise target sites at two scales –
sites that host large numbers of birds (i.e., especially in migration), and those that host moderate
numbers throughout the nonbreeding range.
Habitat loss has particularly significant implications for Sanderlings during migration—a
time when they must put on fat to fuel their long flights—and also in winter (stressful weather).
The potential cost during migration is clear: without enough fuel (fat), Sanderlings may not be
WHSRN – Sanderling Conservation Plan, February 2010, v1.1 37